In his most recent column, Keller poked at Sarah Palin, the former Alaska governor who’s flirting with the notion of making a run for president. Ill-fated that would be.

But Keller’s column — especially its opening observation — revealed more about the dearth of intellectual diversity and contrarian thinking in American journalism than it did about the limited appeal of Sarah Palin.

Keller, the Times executive editor, wrote blithely:

“If the 2012 election were held in the newsrooms of America and pitted Sarah Palin against Barack Obama, I doubt Palin would get 10 percent of the vote. However tempting the newsworthy havoc of a Palin presidency, I’m pretty sure most journalists would recoil in horror from the idea.”

Keller’s probably correct.

Ten percent of the U.S. newsroom vote may even be a generous assessment.

But rather than consider the implications of such intellectual lopsidedness, Keller breezily wrote that “watching Palin answer a question is like watching a runaway train struggling to stay on the rails, and fact-checking her is like fishing with dynamite.”

OK, that’s amusing.

But in acknowledging and then sidestepping the larger matter of viewpoint diversity in the newsroom, Keller left a more compelling issue unaddressed.

A broad-based ongoing discussion about the dearth of intellectual diversity in the newsroom — why so few American journalists self-identify as politically conservative — would be beneficial to American journalism.

As I note in my latest book, Getting It Wrong, which came out last year, intellectual diversity and contrarian thinking are objectives that deserve to be vigorously promoted in American newsrooms.

“It is certainly not inconceivable,” I write in Getting It Wrong, “that a robust newsroom culture that embraces viewpoint diversity, encourages skepticism, invites challenges to dominant narratives, and rewards contrarian thinking would have helped thwart publication of embarrassing tales such as the Washington Post’s ‘fighting to the death’ story about Jessica Lynch.”

To its credit, the Posthas raised the issue of limited intellectual diversity in the newsroom.

Notably, Deborah Howell, the newspaper’s former ombudsman, wrote in mid-November 2008 that more “conservatives in newsrooms and rigorous editing would be two” ways to confront what she termed “the perception of bias” in political coverage. (The week before, Howell had reported a “tilt” in the Post’s 2008 campaign coverage, in Obama’s favor.)

In her column about perception bias, Howell wrote:

“I’ll bet that most Post journalists voted for Obama. I did. There are centrists at The Post as well. But the conservatives I know here feel so outnumbered that they don’t even want to be quoted by name in a memo.”